1. Field of the Invention
The present invention relates generally to a portable information device associated with a home network. More particularly, the present invention relates to a portable information device contributing to the mutual use of the resources of the portable information device and the home appliances connected to a home network.
2. Description of the Related Art
A network connecting to home conventionally meant ground-based TV broadcastings and phone lines over ten years ago. Also, a home network had meant nothing but connection between the TV and VTR or between audio devices because personal computers (PCs) and digital products including a CD player had not been spread home then.
However, the home network has rapidly come to be in the spotlight recently, exploiting the Intranet technology, which has been developed for business use, such as LAN.
The rapid popularization of information devices such as a PC, a printer, and a scanner and the sharp increase of the number of Internet users as well as the diversification of communication and broadcasting services contribute to the progress of the home network. Besides general phone lines, various kinds of communication means such as ISDN line, cellular phone, and PHS have been developed. To add to the ground-based broadcasting, other broadcasting services such as BS and CS analogue broadcastings, CATV, and digital CS broadcasting are being launched. In the audiovisual (AV) industries, digital products such as a MD player, a digital video camera, and a digital still camera have rapidly progressed, expecting that digital videos and digital TVs will further develop. Also, the technology has been introduced that allows home appliances such as a refrigerator, an air conditioner and a microwave oven to be connected to a home network and allows these connected appliances to be remotely operated and maintained.
In the industry of communication devices, it is no wonder any more that cordless phones are used, and mobile communication devices such as a cellular phone and a PHS have remarkably progressed. Personal digital assistants (PDAs) used as personal information management tool also increases in the number of users. A hand-held terminal containing a communication device such as a cellular phone or a PHS appears to serve as e-mail or personal information manager (PIM).
Thus, the portable information devices such as a cellular phone and PDAs have remarkably progressed as well as the home network. The use of portable information devices is however limited to out-of-home uses such as phone calling, data communication, and schedule management, and is isolated from home appliances. Resources and units on a portable information device, such as operation and display units, therefore are not usable for the home network.
Portable information devices such as a cellular phone and PDAs are independently operated on themselves, not intended to be operated by external equipment. If the potable information devices, which are progressing in personalization, share resources of external equipment, they can be exploited effectively.